Caissa Codex
C42

Petrov's Defense: Classical Attack, Staunton Variation

Chess diagram: Petrov's Defense: Classical Attack, Staunton Variation after 8…c6

Type a move and press Enter: e4, Nf3, O-O, or from and to squares like g1f3 (e7e8q to promote). The board is also played with the mouse.

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Statistics from Lichess

143,164 games: White 50.3% / Draw 7.6% / Black 42.2%

The moves played next. Pick one to see it on the board.
Next moveGamesWhite / Draw / BlackW / D / B
78,14078K
21,97722K
20,87621K
9,6589,658
5,2345,234
2,6312,631
1,9641,964
1,7231,723

Rated Lichess games between players rated 1600 to 2500, from the Lichess opening explorer, updated Nov 2, 2026

Engine evaluation

+0.24 The position is about equal

Best play: 9. Re1 Bf5 10. Ng5 Re8 11. Bxe4 dxe4 12. Nc3 Nd7 13. c5 Bc7

Stockfish 19, depth 30, after the line's last move. Scores are in pawns, from White's side.

Overview

Petrov's Defense: Classical Attack, Staunton Variation (ECO C42, Open Games) is a variation of Petrov's Defense: Classical Attack, Marshall Variation, reached after 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. d4 d5 6. Bd3 Bd6 7. O-O O-O 8. c4 c6 (8 moves).

In 143,164 rated Lichess games between players rated 1600 to 2500, White won 50.3%, Black 42.2% and 7.6% were drawn. White's most played move here is 9. Nc3, in 55% of those games.

It continues into one named variation, Petrov's Defense: Classical Attack, Marshall Variation, Chinese Gambit.

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How to play against Petrov's Defense: Classical Attack, Staunton Variation

9. Qc2 scores best for White: 59.3%, with White winning 56.0% and Black 37.5% of 9,658 games. The most played answer, 9. Nc3, scores lowest: 53.2% in 78K games. Stockfish's first choice is 9. Re1.

Main answers: those played in at least 5% of these games. Score: White's wins plus half the draws, in rated Lichess games between players rated 1600 to 2500. How to play against other popular openings

Variations (1)

Other lines from the same position

Instead of 7. O-O O-O 8. c4 c6, the position after Petrov's Defense: Classical Attack, Marshall Variation also goes on to:

Cite this page

Caissa Codex. “Petrov's Defense: Classical Attack, Staunton Variation (C42)”. Lichess data as of 2 Nov 2026. https://chesscodex.org/openings/petrovs-defense-classical-attack-staunton-variation

https://chesscodex.org/openings/petrovs-defense-classical-attack-staunton-variation